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Assuming that card_no and log_entry have VARCHAR or CHAR type, I would first add an index on (card_no, date, last_entry): ALTER TABLE entry_log ADD INDEX card_no__date__last_entry__ix (card_no, date, last_entry) ; and then use this query: SELECT CONCAT(date, ' ', last_entry) AS LAST_LOG FROM entry_log WHERE card_no = LPAD('2948', 32, '0') ORDER ...


Cleanse your data before storing it. Otherwise, INDEXes may be useless. I this particular case, the TRIM function is hiding card_no, making the INDEX on card_no useless. This SELECT would run a lot faster because of the index: SELECT MAX(CONCAT(date, ' ', last_entry)) AS LAST_LOG FROM entry_log WHERE card_no = '2948' OK, you don't like the ...

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